This application is based on Japanese Patent Application No. Hei 11-106914 filed on Apr. 14, 1999, the contents of which is incorporated herein by reference.
1. Field of the Invention
The present invention relates to a stator of a rotary electric machine having an improved dielectric strength at an edge of an axial inlet of a slot and a manufacturing method of the same.
2. Description of Related Art
It is known that a construction is disclosed in JP 58-157349A for improving a dielectric strength at an edge of a slot formed on a stator of rotary electric machine. In this prior art, wavy creases are previously formed on a portion of an insulating member where the insulating member contacts an edge of a slot. After that, an end portion of the insulating member extended from the slot is heated and expanded. As a result, easiness for inserting a conductor into the slot is improved, and insulation is maintained by inserting the insulating member to separate the conductor and the edge.
However, in the prior art, a heating and forming die is pressed on the stator core when the end portion is heated and expanded. The insulator is pressed on the edge of the slot, and a thickness is decreased. Therefore, there is a possibility of insulation failure if the conductor is compressed between the die and the edge of the slot and is deformed.
The present invention addresses these drawbacks by providing an improved stator arrangement.
It is therefore an object of this invention to provide a stator having improved dielectric strength at the edge of the slot and a manufacturing method.
According to the present invention, an expanded end is formed on an insulating member. The insulating member is moved toward a side of the expanded end before a conductor is inserted from the expanded end.
Therefore, an easiness to insert the conductor is improved due to the expanded end. An additional damage on the deformation mark is prevented when the conductor is inserted. Therefore, an insulation failure at a deformation mark is prevented.
It is preferred that the deformation mark is positioned in the out of the slot after a conductor is inserted. In this construction of the stator, an additional damage on the deformation mark is prevented during the conductor is inserted. A thickness of the insulating member positioned between an edge of a slot and the conductor is maintained thicker than the thinned deformation mark.